AUTHOR=Ahmad Farooq , Diez Julio Javier 

TITLE=Spanish ecological battleground: population structure of two invasive fungi, Cryphonectria parasitica and Fusarium circinatum

JOURNAL=Frontiers in Plant Science

VOLUME=14

YEAR=2023

URL=https://www.frontiersin.org/journals/plant-science/articles/10.3389/fpls.2023.1310254

DOI=10.3389/fpls.2023.1310254

ISSN=1664-462X

ABSTRACT=<sec><title>Introduction</title><p>Invasive fungi distributed worldwide through globalization have caused devastating diseases in different forests, causing economic and ecologic disturbances. Two such invasive species are <italic>Cryphonectria parasitica</italic> and <italic>Fusarium circinatum</italic>, which were introduced to Europe from North America, separated temporally: <italic>C. parasitica</italic> was introduced about nine decades ago, whereas <italic>F. circinatum</italic> was introduced around two decades ago. As <italic>C. parasitica</italic> had a longer time to undergo genetic changes, we hypothesized that it has higher genetic diversity than the recently introduced <italic>F. circinatum</italic> in Spain. In addition, we studied the genetic characterization of both fungi present in similar ecological conditions in Northern Spain with the aim of providing data for biocontrol measures.</p></sec><sec><title>Methods</title><p>Molecular genetic markers were used to test these hypotheses, including mating type and DNA sequencing of internal transcribed spacer (ITS) regions. In addition, we used vegetative compatibility (VC) type markers in <italic>C. parasitica</italic> as the information about VC type is essential to apply biocontrol against the fungus.</p></sec><sec><title>Results and discussion</title><p>All the isolates of <italic>C. parasitica</italic> from the studied area belonged to only one VC type (EU-1) and one mating type (MAT-2). However, three distinct haplotypes of <italic>C. parasitica</italic> were identified through ITS sequencing, showing that multiple introductions might have happened to Cantabria. Among <italic>F. circinatum</italic>, no diversity was observed in ITS and MAT loci in the studied area but isolates from other Spanish regions showed the presence of both mating types. Overall, <italic>C. parasitica</italic> had higher genetic diversity than <italic>F. circinatum</italic>, despite both organisms appearing to reproduce clonally. This study helped understand the invasion patterns of <italic>C. parasitica</italic> and <italic>F. circinatum</italic> in northern Spain and will be useful in applying biocontrol measures against both pathogens.</p></sec>